The subject matter disclosed herein relates generally to underground cables and, more particularly, to a device and method for detecting and locating defects in underground cables.
Underground cables enable electricity to travel from a power plant to residential and commercial customers. The cables include conductors where the electric current flows, and insulation that surrounds the conductors to inhibit the electric current from flowing outside the conductors. The cable insulation may deteriorate over time and become faulty, causing defects such as partial discharge. A partial discharge refers to an abrupt change in current in the cable that may be generated during the breakdown of insulation or when current arcs between the cable and another insulator. Protracted partial discharge may further erode the cable insulation and result in a total breakdown of insulation, or complete cable failure.
Monitoring the underground cables to detect defects such as partial discharge may be desirable in order to prevent a total breakdown of insulation or complete cable failure. When cables are monitored, a defect may be found before a complete breakdown occurs. The cable may be repaired or replaced to eliminate defects. Some monitoring systems may detect that a defect exists; however, such monitoring systems may fail to determine an accurate location on the cable where the defect can be found. With an accurate defect location, the task of repairing or replacing cables may be simplified. Therefore, a need exists for a device and/or method that can detect and accurately locate defects in underground cables.